Vaulting pole with helical winding having spaced apart convolutions



Jan. 27, 1970 J. M. LINDLER 3,491,999

VAULTING POLE WITH HELICAL WINDING HAVING SPACED APART CONVOLUTIONS 2Sheets-Sheet 1 Filed March 10, 1967 m E 0 W m a M a Jan. 27, 1970 J. M.LINDLER 3,491,999

VAULTING POLE WITH HELICAL WINDING HAVING SPACBD APART CONVOLUTIONSUnited States Patent 3,491,999 VAULTING POLE WITH HELICAL WINDING HAVINGSPACED APART CONVOLUTIONS James Monroe Lindler, Lexington, S.C.,assignor to C0- lumbia Products Company, Columbia, S.C., a corporationof South Carolina Filed Mar. 10, 1967, Ser. No. 622,193 Int. Cl. A63!)5/06 US. Cl. 27259 7 Claims ABSTRACT OF THE DISCLOSURE A vaulting poleof hollow construction with an integral helical winding along at least aportion of the length of the pole, and a method of making the same. Thepole has a glass fiber reinforced tube, and a helical winding havingspaced apart convolutions of resin-impregnated glass fibers which iscured and integrally bonded to the tube.

This invention relates generally to vaulting poles for use in the sportof pole vaulting, and more particularly to vaulting poles comprised ofglass fiber reinforced plastics.

In the sport of pole vaulting, the vaulter is required to clear acrossbar releasably mounted between two uprights which are spaced apartby about 12 feet. In approaching the uprights and the crossbar, thevaulter generally carries the vaulting pole with his hands spaced-apartby about 2 /2 feet and runs about 100 to 140 feet to build up speed. Ashe nears the uprights, the vaulter generally plants his vaulting pole ina slideway positioned directly below the crossbar which acts as a pivotpoint, shifts his lower hand up the pole until it is next to his upperhand, and then raises both hands as far as possible over his head beforehe leaves the ground. He is then in a position to exert the full pullingpower of both arms to raise his body and to help him swing up his legs.He then runs oif the ground, leaving his body hanging by his hands aslong as possible, and lets his legs swing upward and to the side of thecrossbar. When his legs are above the crossbar, the vaulter generallyshoots his legs higher by means of a strong pull on the pole, and thenturns his body face downward to convert his pulling force into a pushingforce. At this point the crossbar lies beneath his stomach such that hisfeet are on one side of the crossbar and his head and shoulders are onthe other side. Finally, the vaulter carries his body across thecrossbar in a fly-away and releases the vaulting pole.

The foregoing technique requires a high degree of coordination, timing,speed of approach and gymnastic ability on the part of the vaulter.Moreover, one of the essential elements of the technique is a sure andsecure grip on the vaulting pole at all times. Further, it has beenfound desirable that the vaulting pole bend along its length under thevaulters weight so as to provide a spring-like catapult effect upon thevaulter, and thereby aid the vaulter in clearing the crossbar.

Heretofore, vaulting poles have been made of wood, such as bamboo, andalso of metal such as aluminum, and of various lengths and diameters.Vaulting poles have also been heretofore made of glass fiber, such poleshaving been found preferable over wood and metal poles due to theirstrength, light weight, resilience, and relative consistency ofcharacteristics under varying environmental conditions.

Briefly, this invention provides a glass fiber reinforced vaulting poleof greater flexural characteristics than heretofore used vaulting poles,including those comprising glass fiber. Further, the invention providesa vaulting pole having an integral helical grip winding which willremain 3,491,999 Patented Jan. 27, 1970 relatively consistent incharacteristics during the life of the vaulting pole, and which willenable a vaulter to grip the vaulting pole firmly and securely duringall the phases of vaulting described above.

The glass fiber reinforced vaulting pole described herein is formed ofan elongated tube of hollow construction having an internal layer ofknitted glass fiber tape or yarn impregnated with a thermosetting resin,an external sheath of longitudinal glass fiber filaments impregnatedwith a thermosetting resin, and an integral external helical gripwinding of glass fibers also impregnated with a thermosetting resin.Adjacent turns of the winding are spaced apart about inch along thelength of the vaulting pole and have a winding pitch of about 4 inch,and the winding protrudes about inch from the sheath of longitudinalglass fiber filaments.

In forming the vaulting pole, a knitted glass fiber tape pre-impregnatedwith a thermosetting resin is wrapped about a mandrel, andpre-impregnated longitudinal glass fiber filaments are then laid aboutthe tape substantially parallel to the axis of the mandrel. A pluralityof cellopane tapes are then helically wound about the longitudinal glassfiber filaments, and the assembly is formed into an integral unit bycuring the resins, as by positioning the assembly within an oven andheating the same through a range of curing temperatures. The cellophaneand mandrel are then removed, the surface of the integral unit isroughened as by sanding, and a helical winding of glass fiberspre-impregnated with a thermosetting resin is ap plied to the surface ofthe unit. After curing and hardening of the winding, as by standingovernight, the winding becomes integrally bonded to the remainder of theunit. The integral unit is then cut to the desired length and fittedwith a pivot cap at one end and a plug at its other end.

It is an object of the invention to provide a vaulting pole having anintegral helically-configured gripping area.

It is another object of the invention to provide a glass fiberreinforced vaulting pole which has a helical winding to provide agripping area for the vaulter.

It is another object of the invention to provide a glass fiberreinforced plastic vaulting pole having improved flexural properties.

It is another object of the invention to provide a method of making avaulting pole having an integral helicallyconfigured surface.

These and other objects and advantages of the invention will be apparentand be more fully understood from the following description and claimsconsidered in conjunction with the accompanying drawings in which:

FIG. 1 illustrates a perspective view of a glass fiber reinforcedplastic vaulting pole of the invention in use during an ascent phase ofa vault;

FIG. 2 illustrates a plan view of a vaulting pole of the invention,having a helical winding on the outer surface;

FIG. 3 is a fragmentary perspective view, partly in cross section, of avaulting pole of the invention;

FIG. 4 is a broken cross sectional view of the ends of a vaulting poleof the invention with a pivot cap and plug in place at the ends of thepole;

FIG. 5 illustrates a view taken on line 55 of FIG. 2;

FIG. 6 illustrates a flow diagram of a method of making a vaulting poleof the invention; and

FIG. 7 illustrates a perspective view of a manner of applying thehelical winding to the vaulting pole.

Referring to the figures and in particular to FIGS. 2 to 5, vaultingpole 10 comprises a cylindrical hollow tube 11 and a helical winding 12which is coiled around the entire length of the hollow tube 11.

Tube 11 is formed as a laminated integral unit with an interior layer ofknitted glass fiber tape impregnated with an epoxy resin, and anexterior layer or sheath of longitudinal glass fiber filaments alsoimpregnated with an epoxy resin. The glass fiber tape is wrapped on amandrel in overlapping helical convolutions, while the glass fiberfilaments are laid over the convoluted tape substantially parallel tothe longitudinal axis of the tube to form a concentric sheath about thetape. The respective resins of the tape and filaments serve tointegrally bond the tape and filaments together to form the hollow tube10. Alternatively, instead of using a knitted glass fiber tape, a singlelayer or double layer of right hand and left hand close-wound glassfiber yarn impregnated with an epoxy resin can be used.

A helical winding 12 is integrally formed on the hollow tube 11 by aplurality of closely related epoxy impregnated glass fibers. These glassfibers are wound in a continuous manner about the hollow tube, as showin FIG. 7 for example, for the entire length of the tube 11, and areintegrally bonded to the tube 11 through curing of the resin of thewinding 12. Adjacent convolutions of the helical winding 12 areuniformly spaced apart, by for example about A inch, along the length oftube 11, and are wound on the tube with a pitch, for example, of about Ainch. Further, these convolutions are sized to project from the surfaceof the tube 11 a distance of, for example, about inch, and to be a widthof, for example, about inch.

As shown in FIG. 4, a pivot cap 13 is in engagement with one end of thevaulting pole and a plug 14 is in engagement with the opposite end ofthe pole to seal the respective ends of the pole. Pivot cap 13 iscomprised of a resilient, slip-resistant material such as rubber. It hasa tenon portion 15 with a tapered internal recess 16, and asubstantially semi-spherical head portion 17. The two portions 15, 17 ofthe pivot cap are integral with one another, the head portion 17extending over the tenon portion 15 in a manner to form an annularrecess 18 therebetween. This annular recess 18 receives one end of thevaulting pole 10 while the tenon portion 15 is bonded by adhesive, forexample an epoxy adhesive within the vaulting pole 10. Plug 14 is of amaterial such as cork, and is sealingly secured within the opposite endof the vaulting pole 10 by means of friction or a suitable adhesive.

Pivot cap 13 and plug 14 serve to seal the interior of the vaulting pole10 against the entrance of dirt, moisture or other foreign matter. Inaddition, pivot cap 13 serves as a means to frictionally engage aslideway or vaulting starting recess or block (not shown) on the ground19 so as to permit the vaulting pole 10 to be planted and pivoted duringa vaulters ascent over an elevated crossbar 20 releasably mountedbetween a pair of uprights 21 (FIG. 1).

Describing a method of making vaulting pole 10 now in further detail andreferring to FIG. 6, initially an epoxy-impregnated knitted glass fibertape 22 having a width of about 1 /2" is wrapped in a helical mannerabout a cylindrical mandrel 23 which may be of steel. The tape 22 iswrapped with a pitch or lead of about 0.35 to 0.40 inch per revolutionso that successive convolutions of the tape overlap and form essentiallyfour layers of tape on the mandrel. Next, a plurality ofepoxy-impregnated glass fiber filaments 24 are applied about thetape-wound mandrel to form a sheath each of the filaments being laidsubstantially parallel to the longitudinal axis of the mandrel. Then,four layers of tape 25 such as cellophane are helically wound about thesheath of longitudinal filaments in overlapping convolutions to form apackaged assembly, two layers of tape 25 extending clockwise about thesheath of longitudinal filaments, and two layers extendingcounterclockwise about the sheath. The assembly is then hung in an ovenwhere the epoxy resins are cured under heat to form the tape andfilaments into an integral hollow tube. The oven heats the assembly at150 F. for four hours, then at 175 F. for one hour,

then at 200 F. for one hour, then at 210 F. for one hour and then at 220for two hours. Finally, the oven is shut off and allowed to cool for twohours before the assembly is removed.

After the assembly is taken from the oven, the mandrel is removed fromthe hollow tube as by pulling with a hydraulic puller, and thecellophane tapes are removed as by the impingement of hydraulic orpneumatic fluid jets. Next, the outside surface of the hollow tube isroughened as by being sanded, and a helical winding 12 ofepoxy-impregnated glass fibers is then applied around the hollow tube ona pitch of about A" (FIG. 7). The winding spreads to about /s" widthwhile taking on a thickness of about After standing at room temperatureovernight, winding 12 becomes cured and hardened integrally to thehollow tube so as to form a length of vaulting pole.

The formed vaulting pole length can then be lightly sandedlongitudinally to remove small projections and subsequently painted aswith a white finish. When the finish has dried, the vaulting pole is cutto the desired length and tested. For example, the vaulting pole may beof any suitable overall diameter, such as from 1% to 1% inches, and anysuitable wall thickness, such as from to /8 inch, and may be cut to anydesired length, such as from 12 to 16 feet. Subsequently, the pivot cap13 and plug 14 are fitted to the vaulting pole 10 and marketing decals(not shown) are applied.

The invention provides a vaulting pole with a grip winding withuniformly spaced convolutions which enable a vaulter to grip thevaulting pole more securely and surely than heretofore, especiallyduring the sequence of pulling and pushing vaulting phases near the topof the vaulters ascent. Since the grip winding is an integral part ofthe vaulting pole there can be no slippage of the winding relative tothe vaulting pole nor is there any possibility of the winding becomingunraveled or displaced on the pole during the course of use.

In addition, the invention provides a glass fiber reinforced vaultingpole which possesses greater flexural properties than possessed by priorglass fiber vaulting poles. In this regard, it has been found bycomparative tests with heretofore used glass fiber vaulting poles thatthe vaulting pole of this invention has about 10% greater bendingstrength than equivalent diameter poles, as well as a greater degree offlexure and resilience. The glass fiber reinforced vaulting poles ofthis invention have been bent such that the ends of the pole each definean angle of with respect to the plane between the ends of the polewithout the pole cracking or becoming permanently deformed.

It is believed that the greater bending strength and flexure of thepoles of this invention are developed through the coaction between thecylindrical hollow tube 11 and the helical winding 12. That is, as thehollow tube flexes under the forces imposed by the vaulter (see FIG. 1),the helical winding acts as reinforcement in tension against the hollowtube and, where other poles might fail under certain bending stressesand strains, the helical winding of the pole of the invention serves toprevent failure at these stresses and strains. Further, it is alsobelieved that the greater resilience of the poles of this invention areat least in part obtained because the hollow tube and helical windinghave different spring characteristics due to the structural shape andformation of each, and the spring characteristics augment and complementeach other to provide a greater degree of resiliency and reaction duringthe fly-away phase than heretofore achieved. This adds an additionalcatapult-like effect to the vaulters own capabilities and the bendingstrength qualities of the pole to enable the vaulter to vault greaterheights than might be otherwise obtained.

Having described particular embodiments of invention, it is not intendedthat it be so limited, as changes may be readily made therein withoutdeparting from the scope of the invention. Accordingly, it is intendedthat the foregoing Abstract of the Disclosure and description, and theaccompanying drawings be interpreted as illustrative and not in alimiting sense. For example, while epoxy resins have been referred toabove, other resins can also be used, such as for example, a polyesterresin.

What is claimed is:

1. A vaulting pole characterized by a tube comprised ofresin-impregnated glass fibers; and a helical winding comprised ofresin-impregnated glass fibers which is integral with said tube andextends along at least a portion of the length of the tube on theoutside surface thereof, wherein adjacent convolutions of said helicalwinding are spaced-apart from one another and wherein the convolutionsof said helical winding extend outwardly from the outside surface ofsaid tube.

2. A vaulting pole as set forth in claim 1 further comprising a pivotcap engaged with one end thereof and a plug engaged with the oppositeend thereof.

3. A vaulting pole as set forth in claim 2 wherein said pivot cap andsaid plug are each engaged with said tube in a fluid-tight relationshiptherewith.

4. A vaulting pole as set forth in claim 1 further comprising a pivotcap sealingly engaged with one end of said pole and a plug sealinglyengaged with the opposite end thereof, and wherein adjacent convolutionsof said helical winding are spaced apart by about A inch and eachconvolutionof said helical winding extends about inch from the outsidesurface of said tube.

5. A vaulting pole as set forth in claim 4 wherein said pivot cap iscomprised of rubber and said plug is comprised of cork.

6. A vaulting pole comprising a tube and an integral helical winding ofresin impregnated glass fibers extending along at least a portion of thelength of said tube, said helical winding having a plurality ofconvolutions disposed in spaced apart relationship from one another andprojecting from the surface of said tube.

7. A vaulting pole as set forth in claim 6 wherein said tube iscomprised of resin impregnated glass fibers.

References Cited UNITED STATES PATENTS 2,822,175 2/ 1958 Redmond.

3,140,873 7/1964 Goodwin 273-8l.5 3,198,520 8/1965 Ahmuty 27381.6 XR3,379,220 4/1968 Kiuchi et a1 272-59 ANTON O. OECHSLE, Primary ExaminerR. W. DIAZ, JR., Assistant Examiner US. Cl. X.R. 15 6-l87

